The present invention relates to digital data processing, and in particular to digital data input devices for use by individuals with physical disabilities.
In the latter half of the twentieth century, there began a phenomenon known as the information revolution. While the information revolution is a historical development broader in scope than any one event or machine, no single device has come to represent the information revolution more than the digital electronic computer. The development of computer systems has surely been a revolution. Each year, computer systems grow faster, store more data, and provide more applications to their users.
The reduced cost of computing and the general availability of digital computing devices has brought an explosion in the volume of information available on such devices, and in the variety of applications to which such devices are put. For some years now, inexpensive xe2x80x9cpersonal computersxe2x80x9d have been available for personal use at home or for the use of a single individual at a place of business. Increased miniaturization has made it possible to design portable xe2x80x9claptopxe2x80x9d computers and personal digital assistants (PDAs). These devices, together with the prevalence of the Internet, have brought digital information and computing capabilities to the public on a mass scale.
One consequence of these developments is that individuals who, for whatever reason, lack access to computer technology, are at a disadvantage, and this disadvantage grows in significance with each passing year. For example, it is now common for colleges and universities to communicate with students concerning schedules, assignments, grades and so forth, over the Internet. In some institutions, this reliance on the Internet has reached an extent that it is difficult or impossible to complete required courses without use of the Internet, a trend which is likely to continue. Such a use of digital technology and the Internet shows signs of further expansion into high school and lower level curricula.
Despite these developments, many individuals remain either unable to perform basic tasks involving the use of a computer, or less than proficient in the performance of such tasks. There are many and various reasons for these deficiencies, not all of which are addressed herein. For some individuals, lack of computer capability is due primarily or partially to physical handicaps, which make it difficult or impossible for the individual to use conventional digital input and output devices.
Physical handicaps may assume various forms, not all of which are immediately apparent. One particular form of physical handicap which may affect the individual""s ability to use a computer is limited hand motion. As used herein, limited hand motion means an inability to use the hands and fingers to the full range and extent typical of an unimpaired individual, but does not imply total paralysis of the hand. Such a handicap may be caused by repetitive strain injury, arthritis, or other cause. An individual with limited hand motion may be able to perform many or nearly all everyday tasks using his hands, such as grasping an object, turning a light switch, and so forth. Therefore, the individual may not appear to be handicapped at all. Often, the individual in question can, in fact, move the affected joints of the hand within a range which might be considered normal, but to do so is painful. In some cases, it may only be painful if done on a frequent basis, as might be involved in typing on a conventional computer keyboard. It might even be the case that susceptibility to future injury or aggravation of an underlying condition can be predicted, so that although moving the affected joints of the hand in a normal full range of motion elicits no immediate symptoms such as pain, to do so on a repetitive basis might be expected to cause or aggravate injuries.
Limited hand motion is a very common problem, yet it is often neglected in human factors planning in favor of more severe handicaps. For example, persons with no hand motion (or no hands) at all can use certain alternative special input devices, such as voice recognition or sensors attached to feet or other parts of the body. It follows that individuals with limited hand motion could use such devices as well. But such devices provide a form of input which is either slow, error prone, or in some other respect generally inferior to the conventional keyboard.
It would be desirable to provide individuals with limited hand motion with a more suitable form of input device, which is customized to their particular handicap, and which approaches or equals the conventional keyboard in input efficiency.
A simulated keyboard data input device comprises a hand motion sensing apparatus and a sensor interpreter. The sensing apparatus is preferably in the form of a glove (or pair of gloves) which fits over the hand (or hands) of a user, within which are mounted multiple sensors capable of detecting minute voluntary motion of the fingers, the minute voluntary motion being significantly less than typically required for activation of keys in a conventional computer keyboard. A sensor interpreter in a receiving digital device is configured for an individual user to recognize different finger movements or combinations of finger movements, consistent with the individual user""s capability, as respective characters corresponding to the keys of a keyboard. Once the simulated keyboard input device is configured, the user xe2x80x9ctypesxe2x80x9d text on the simulated keyboard by repeating those combinations of minute finger motion of which the user is capable to produce keyboard characters from the sensor interpreter.
In the preferred embodiment, the sensor interpreter comprises a virtual keystroke detector and a key decoder. The virtual keystroke detector is preferably an algorithmic function which periodically scans the sensors and detects local deflection maxima as virtual keystrokes. The key decoder is preferably a suitably trained artificial neural network, for which the inputs are sensor data for the detected virtual keystrokes and the outputs are keyboard characters. Suitable training data for the neural network may be obtained, e.g., by requesting the user to xe2x80x9ctypexe2x80x9d various sample texts and conforming the sensor results to the desired output. The neural network is preferably emulated by programming code executing in a programmable processor.
Preferably, the sensors in the data glove are coupled via cable to a sensor receiver, which is a small, portable special-purpose electronic device which can conveniently be worn by the user, fit in a pocket or attached to clothing, and which in turn communicates with a digital computer. The virtual keystroke detector is preferably housed in the receiver, while the key decoder neural network is implemented in programming on the digital computer. However, the sensor interpreter functions could alternatively be implemented entirely in the digital computer, on entirely in a special-purpose device such as the sensor receiver.
In one aspect of the preferred embodiment, the user wears a pair of gloves to interpret motion of all ten digits of the hands. However, in an alternative aspect, a user with use of only a single hand might wear a single glove, or gloves might be used for users with fewer than ten operative fingers. Arbitrary xe2x80x9cchordxe2x80x9d combinations of finger movements may be employed to obtain a desired number of keyboard characters for individuals having use of fewer than ten fingers.
A simulated keyboard input device as described herein thus provides the capability for individuals who are physically unable to use a conventional keyboard in the intended manner to nevertheless enter data in a manner similar to that of non-disabled users of a conventional keyboard, and at a level of efficiency which may in some circumstances approximate that of the non-disabled user.
The details of the present invention, both as to its structure and operation, can best be understood in reference to the accompanying drawings, in which like reference numerals refer to like parts, and in which: